Hi Nigel,
My device is a Linksys WRT54GS which as I said, and as you know is a broadband router.  I understand the bit about local and public addresses.  As your WAP plugs directly into the ethernet connection on the Iberbanda box and so does mine, they would appear to essentially perform the same function in their ability to allow shared internet connection and as Paul was talking Iberbanda, I couldn't see the relevence to telephone lines and ADSL.  Anyway, hopefully our discussion will allow Paul to make a choice that works for him and not just confuse the socks off him.  :o